package com.wires.lu.practice;



import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * 题目：一个初始值魏0的便利，两个线程对其交替操作，一个加一一个减一，来5轮
 *
 *   1 线程       操作          资源类
 *   2 判断       干活          通知
 *   3 防止虚假唤醒机制
 */

class ShareData{//资源类
    private int number=0;

    private Lock lock=new ReentrantLock();

    private Condition condition=lock.newCondition();

    public void increment() throws  Exception{
        lock.lock();
        try{
            //判断
            while(number!=0){
                //等待 不能生产
                condition.await();
            }
            //干活
            number++;
            System.out.println(Thread.currentThread().getName()+"\t"+number);
            //3 通知唤醒
            condition.signalAll();
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            lock.unlock();
        }
    }

    public void decrement() throws  Exception{
        lock.lock();
        try{
            //判断
            while(number==0){
                //等待 不能生产
                condition.await();
            }
            //干活
            number--;
            System.out.println(Thread.currentThread().getName()+"\t"+number);
            //3 通知唤醒
            condition.signalAll();
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            lock.unlock();
        }
    }

}


public class ProdConsumer_traditionDemo {


    public static void main(String[] args) {
        ShareData shareData=new ShareData();

        new Thread(()->{
            for (int i = 0; i < 5; i++) {
                try {
                    shareData.increment();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        },"AA").start();

        new Thread(()->{
            for (int i = 0; i < 5; i++) {
                try {
                    shareData.decrement();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        },"BB").start();
    }

}
